Spark-plug-cooling device



E T. CURRAN SPARK PLUG COOLING DEVICE Filed JulyA 1a 1921 AT' RNEYS.

Patented Dec. 8, 1925. 5?"

UNITED/STATES PAT-ENT! EDWARD T. CURRAN, or; DETROIILYMVICHIGAN. Y y'srARKfrLUG-cooriive DEVICE."

Appiicationmed Juiy is, 192i. yserial No; 485,459.

To all whom 'it may concern: j

Be itknown that I, EDWARDv T. CURRAN, a citizen of the United States,residing at Detroit, in the county of Wayne and the State of Michigan,have invented a certain new and useful Spark-Plug-Cooling Device,

of which the following is a specification.

This invent-ion is a spark plug cooling device and the object Vof theinvention is to provide simple andelfective'meansfor keeping spark plugsof internal combustion engines cool. It is a well known fact that thethe plug passes through asubstantiallytubul'ar formation surrounded by abody of cooling fluid. VThe shank ofthe plug fis thus fairly well cooledby fact'that the heat absorbed by the shank from the explosion in the"cylinder is conducted through the relatively thin wallof the jacket tothe water therein. vHowever the partsy of the'plug di.' r'ectly abovethecshank are not intimately in contact with the walls'of-the jacket butare surrounded by air, which, being a poor conductor cf 'heat causesthe` plug 'to unduly heat up." In vpractically every instance they;tapped hole for the plug is in the base ofr the relatively wide bowl orrecess in the '-cyll;

I' inder head and' sincethe lower portion of the plug Vseats in the baseofsuch bowl the circulation of'air from the fan does lnot eihcientlycoolthe plug. 'n v With the foregoing considerations in mind Ihaveexperiniented extensively with the robleins under consideration andhave found that I can efficiently conduct the'heat fromthe plugrto thecoolingv fluid within the jacket of the cylinder head by positioningwithin the bowl a heat conducting bridge which is maintained inengagement with the outer wall of the water'jacket anidalso inengagement with the-plug.V The metal einployed inthe manufacture of thisbridge is preferably one of hio'h conductivity so as to rapidly take upthe heat from the plug and conduct it to they wall of the water jacketwhich at' this point in engine Vconstruction is relatively thin. By thisarrangement "I have' found that the'heat 'fromthe plug is rapidly`conducted to the water in the jacket, the

temperature 1 of fwhich water never" exceeds 212.y Practice has-shownthat when the construction described is employedv theheat from the plug`will be so rapidly absorbed that in engines where the plugshave been`l linthe* habit? of heating fto approximately 700or Fahrenheit beymay,through the'employinent of the 'present' invention, they Vopl,

erated forextended periods without heating to a' temperature which is inexcessief 250,

Features of the invention other than those specifiedv will 'be apparentVfrom the follow-k ing detailed description and` claims when read inconjunction with the. accompanying di'awiiigsj i The accompanyingdrawings illustrateone practical embodiment of theinvention, but theconstruction therein shownl is to be understood as illustrative, only,and-'notas defining the limits of the invention;

Figui-e' l is atransverse section cfa Ford cylinder 'head showing' t-hepresent invention associated with'one of the'Y plugsmounted thereon; i i

Figure 2 is a central section perspective of the device of the presentinventionv removed from the cylinder head; and

Figure 3 is a plan view of the device. Vhile the present invention beyassociated with the engine of any make of car,

I have shown for the purpose of illustration Thus in Fig. 1 of thedrawings the cylinder head 5 of the Ford engine is shown in section. Thehead is cored to vprovidethe jacket 6 for the circulation ofthe coolingfluid and is also tapped as at 7 to receive the shank of the spark plug8. v The tapped hole 7 extends through the head 5 at the base of a bowlshaped depression 9 and whenv the plug 8 is screwed linto the hole 7 theshank of the plug extends down through .the cylinder head so that thelpoints of the plug "areeither in or directly adjacent the compressionspace of .Y

the cylinder."

In associating the vpresentinvention .with .the construction describedthe devicefmay los l0 the sameV as embodied in Ford construction.

f" tinuous contact with the superficial surface Van annular casting 10,the outer periphery of which is shaped complementarily to the base ofthebowl shaped depression 9 so that when the casting is placed in thedepression 9 it will seat in the base thereof. The outer vface of thecasting .is preferably provided with a depressed seat 11, while in thecentre ofthe casting is a hole 12 through which the shank of the plug isadapted to extend.

In assembling the parts the casting is v; placed into the bowl shapeddepression and the shank of the pl-ug 8 is thereupon passed through theropening 12 and screwed int-o the tapped hole 7 by means of a wrench orother convenient tool applied to the hexagonal portion common toconventional plugs.

The screwing down of the plug 8 causes the casting 10 to be forced to atight seat in the depression 9 so that the outer periphery of thecasting will come into intimate and conof that portion of the waterjacket wall which it o-ver lies, and at the same time the base ofthehexagonal portion of the plug will be forced toa tight seat on the ledgeor seat 11 of the casting. If the casting 10 is of aluminum, copper orsome other relatively soft and'mall'eable material it will be caused byvpressure exerted thereon by the plug through the assembling of theparts, to conform to the portions with which f f in it will appear thatthe heat will be con- Y eo ducted from the plug through the casting 10to the jacket wall which, being relatively thin, will rapidly conductsuch heat yto the water within the jacket 6V sothat thebuilding up ofheat to hightemperatures within the plug will be impossible. The plugwill thus be kept relatively cool, which cooling has heretofore .beenpossible only through the employment of expensive water and aircirculating mechanism.

I am aware that the present invention, which contemplates the.:employment of a heat conducting bridge broadly, may be made of differentshapes than as shown. in the drawings which shapes will depend on theengine with which it is to be associated. This invention is not limitedto the construction shown, b-ut contemplates the substitution ofequivalents and is broadly as is commensurate with Vthe appended claims.

Having thus fully described the invention what I claim as new and desireto secure by Letters Patent is:

l. A spark plugl cooling device embodying a conducting member one sideof which is shaped complementarily to the depression in acylinder head4,from the base of which depression a tapped spark plug hole ofthecylinder head extends, said member being provided with an openingsubstantially equal to the diameter of said tapped hole, whereby thethreaded shank of the spark plug may be passed through said opening andscrewed into the tapped hole in the cylinder head to bring the plug tola seat on said member and simultaneously force said member to a seat insaid recess.

2. ,A spark plug cooling device embodying a member of conductingmaterial provided with an opening substantially equal in diameter to thediameter of the tapped spark plug hole of an engine cylinder and oneface of which member is shaped to seat on the engine cylinder adjacentsaid spark plug hole, whereby the threaded shank of a conventional plugmayV be passed through the opening l in said member and` screwed intothe .tapped hole of the ycylinder for. the purpose of seating the plug4on said member and simultaneously seating the member onthe cylinderhead. Y

3. A spark plug cooling device embodying an annular member of highlyconductive metal shaped to seat in the bowl shaped depression of acylinder head from the v'base of which depression the tapped spark plughole extends, the inner peripheryof the annular member being formed witha seat fora spark plug whereby .the plug mayv be passed through Vsaidmember and screwed into the plugv hole of the cylinder head to come to atight seat with said member and to force the member to a tight seat withthe cylinder head for the purpose of providing'a heat conducting mediumbetween the plug and the cylinder head, through said medium the heatfrom the plug is conducted to the water jacketV ofthe vcylinder head. .c

4. Spark plug cooling device embodying a disc of metal shaped to seat inthe depression inthe cylinder head from the base of which depression thetapped'spark plug hole leads, said disc being provided with an`openingcoaxial with the tapped hole of the cylinder head, whereby the threadedshank of a spark plug'may be passed through said opening and screwedinto the tapped hole inthe cylinder head to irmly'seatthek plug on thediscy and simultaneously seat the disc in the depression.

' In testimony whereof I have signed the foregoing specification. v

EDWARD T. enanas'.

